Add INVALID_INPUT_DEVICE_ID to IInputConstants

The ID is used to reference invalid input devices before they are
initialized. For consistency the INVALID_INPUT_DEVICE_ID is also added
to the ReservcedInputDeviceId enum.

Test: Tested as part of ag/20002215
Bug: 244516415
Change-Id: I2055e8668780ecbcfdc201422fc1fd5ab3549ab6
diff --git a/include/input/InputDevice.h b/include/input/InputDevice.h
index f4a1523..ac9c5a5 100644
--- a/include/input/InputDevice.h
+++ b/include/input/InputDevice.h
@@ -23,6 +23,7 @@
 #include <unordered_map>
 #include <vector>
 
+#include <android/os/IInputConstants.h>
 #include "android/hardware/input/InputDeviceCountryCode.h"
 
 namespace android {
@@ -346,6 +347,8 @@
         const std::string& name, InputDeviceConfigurationFileType type);
 
 enum ReservedInputDeviceId : int32_t {
+    // Device id representing an invalid device
+    INVALID_INPUT_DEVICE_ID = android::os::IInputConstants::INVALID_INPUT_DEVICE_ID,
     // Device id of a special "virtual" keyboard that is always present.
     VIRTUAL_KEYBOARD_ID = -1,
     // Device id of the "built-in" keyboard if there is one.
diff --git a/libs/input/android/os/IInputConstants.aidl b/libs/input/android/os/IInputConstants.aidl
index 5ce10a4..dab843b 100644
--- a/libs/input/android/os/IInputConstants.aidl
+++ b/libs/input/android/os/IInputConstants.aidl
@@ -35,6 +35,14 @@
     const int INVALID_INPUT_EVENT_ID = 0;
 
     /**
+     * Every input device has an id. This constant value is used when a valid input device id is not
+     * available.
+     * The virtual keyboard uses -1 as the input device id. Therefore, we use -2 as the value for
+     * an invalid input device.
+     */
+    const int INVALID_INPUT_DEVICE_ID = -2;
+
+    /**
      * The input event was injected from accessibility. Used in policyFlags for input event
      * injection.
      */